#include<stdio.h>
#include<math.h>
#include<stdlib.h>
typedef struct point{
	double x;
	double y;
	struct point* next;
}POINT;
int  main()
{
	POINT p;
	scanf("%lf%lf",&p.x,&p.y);
	double dis=sqrt(p.x*p.x+p.y*p.y);
	printf("%.3f\n",dis);

	system("PAUSE");
	return 0;
}
